1,517 research outputs found
Cloning of the cDNAs Coding for Two Novel Molybdo-flavoproteins Showing High Similarity with Aldehyde Oxidase and Xanthine Oxidoreductase
Abstract The cDNAs coding for two novel mouse molybdo-flavoproteins, AOH1 and AOH2 (aldehydeoxidase homolog 1 and 2), were isolated. The AOH1 and AOH2 cDNAs code for polypeptides of 1336 amino acids. The two proteins have similar primary structure and show striking amino acid identity with aldehyde oxidase and xanthine oxidoreductase, two other molybdo-flavoenzymes. AOH1 and AOH2 contain consensus sequences for a molybdopterin-binding site and two distinct 2Fe-2S redox centers. In its native conformation, AOH1 has a molecular weight consistent with a homotetrameric structure. Transfection of the AOH1 and AOH2 cDNAs results in the production of proteins with phenanthridine but not hypoxanthine oxidizing activity. Furthermore, the AOH1 protein has benzaldehyde oxidizing activity with electrophoretic characteristics identical to those of a previously identified aldehyde oxidase isoenzyme (Holmes, R. S. (1979) Biochem. Genet. 17, 517–528). The AOH1 transcript is expressed in the hepatocytes of the adult and fetal liver and in spermatogonia. In liver, the AOH1 protein is synthesized in a gender-specific fashion. The expression of AOH2 is limited to keratinized epithelia and the basal layer of the epidermis and hair folliculi. The selective cell and tissue distribution of AOH1 and AOH2 mRNAs is consistent with the localization of the respective protein products
Numerical Prediction of Cavitation Inception in Centrifugal Impellers
Cavitation is a fundamental issue in pump design since it yields significant decrease of performances and pump life, damaging impeller surfaces and triggering harmful flow instabilities. This topic is usually addressed through costly experimental tests. The aim of this paper is to assess numerical methodologies for the correct evaluation and prediction of the cavitation inception in centrifugal impellers during the design phase. Preliminary analyses were performed to individuate the most promising approach by using two cavitation models on a 2D test case representing the NACA 0009 hydrofoil. Then, two CFD approaches were considered for the evaluation of the NPSHr in actual pumps. RANS two-phase calculations including the selected cavitation model were performed on a geometry provided by WEIR Gabbioneta srl. Monophase simulations have been performed as well and an in-house heuristic model has been proposed to evaluate the NPSHr curve from a non cavitating pressure field. The heuristic post-processor has been tuned using both the two-phase and the monophase data, and validated using the available experimental values provided by WEIR Gabbioneta srl
X-ray management in electrophysiology: a survey of the Italian Association of Arrhythmology and Cardiac Pacing (AIAC)
Radiation use in medicine has significantly increased over the last decade, and cardiologists are among the specialists most responsible for X-ray exposure. The present study investigates a broad range of aspects, from specific European Union directives to general practical principles, related to radiation management among a national cohort of cardiologists
Plasmon-enhanced circular dichroism spectroscopy of chiral drug solutions
We investigate the potential of surface plasmon polaritons at noble metal
interfaces for surface-enhanced chiroptical sensing of dilute chiral drug
solutions with nano-litre volume. The high quality factor of surface plasmon
resonances in both Otto and Kretschmann configurations enables the enhancement
of circular dichroism thanks to the large near-field intensity of such
plasmonic excitations. Furthermore, the subwavelength confinement of surface
plasmon polaritons is key to attain chiroptical sensitivity to small amounts of
drug volumes placed around 100 nm by the metal surface. Our
calculations focus on reparixin, a pharmaceutical molecule currently used in
clinical studies for patients with community-acquired pneumonia, including
COVID-19 and acute respiratory distress syndrome. Considering realistic dilute
solutions of reparixin dissolved in water with concentration 5 mg/ml and
nl volume, we find a circular-dichroism differential absorption enhancement
factor of the order 20 and chirality-induced polarization distortion
upon surface plasmon polariton excitation. Our results are relevant for the
development of innovative chiroptical sensors capable of measuring the
enantiomeric imbalance of chiral drug solutions with nl volume
Acute heart failure in patients with acute aortic syndrome: Pathophysiology and clinical-prognostic implications
Aims Although acute heart failure (AHF) is a potential complication of acute aortic syndromes (AAS), its clinical details and management implications have been scarcely evaluated. This study aimed to assess prevalence, pathophysiological mechanisms, impact on treatment, and in-hospital mortality of AHF in AAS. Methods and results Data were collected from a prospective AAS registry (398 patients diagnosed between 2000 and 2013). Patients with AHF were identified by the presence of dyspnoea as the presentation symptom or radiological signs of pulmonary congestion or cardiogenic shock, including patients with cardiac tamponade (CT). AHF frequency was 28% (Stanford type A 32% vs. type B 20%, P = 0.01). Four mechanisms leading to AHF were identified, alone or in combination: CT (26%), aortic regurgitation (25%), myocardial ischaemia (17%), and hypertensive crisis (10%). In type A patients, aortic regurgitation and CT were the most frequent mechanisms, whereas myocardial ischaemia and hypertensive crisis were the most frequent in type B patients. Although no difference was noted for diagnostic times, AHF at presentation led to a longer surgical delay in type A AAS. In-hospital mortality was higher in patients with AHF compared with those without (34% vs. 17%, P < 0.001). After multivariable analysis, AHF was associated with increased risk of in-hospital death (adjusted odds ratio 1.97, 95% confidence interval 1.14-3.36, P = 0.014). Conclusion AHF occurs in more than a quarter of patients with AAS of both type A and type B, is due to a variety of pathophysiological mechanisms, and is associated with increased surgical delay and in-hospital mortality. © 2015 The Authors European Journal of Heart Failure © 2015 European Society of Cardiology
Economic analysis of remote monitoring in patients with implantable cardioverter defibrillators or cardiac resynchronization therapy defibrillators in the Trento area, Italy
IntroductionRemote monitoring (RM) technologies have the potential to improve patient care by increasing compliance, providing early indications of heart failure (HF), and potentially allowing for therapy optimization to prevent HF admissions. The aim of this retrospective study was to assess the clinical and economic consequences of RM vs. standard monitoring (SM) through in-office cardiology visits, in patients carrying a cardiac implantable electronic device (CIED).MethodsClinical and resource consumption data were extracted from the Electrophysiology Registry of the Trento Cardiology Unit, which has been systemically collecting patient information from January 2011 to February 2022. From a clinical standpoint, survival analysis was conducted, and incidence of cardiovascular (CV) related hospitalizations was measured. From an economic standpoint, direct costs of RM and SM were collected to compare the cost per treated patient over a 2-year time horizon. Propensity score matching (PSM) was used to reduce the effect of confounding biases and the unbalance of patient characteristics at baseline.ResultsIn the enrollment period, N = 402 CIED patients met the inclusion criteria and were included in the analysis (N = 189 patients followed through SM; N = 213 patients followed through RM). After PSM, comparison was limited to N = 191 patients in each arm. After 2-years follow-up since CIED implantation, mortality rate for any cause was 1.6% in the RM group and 19.9% in the SM group (log-rank test, p < 0.0001). Also, a lower proportion of patients in the RM group (25.1%) were hospitalized for CV-related reasons, compared to the SM group (51.3%; p < 0.0001, two-sample test for proportions). Overall, the implementation of the RM program in the Trento territory was cost-saving in both payer and hospital perspectives. The investment required to fund RM (a fee for service in the payer perspective, and staffing costs for hospitals), was more than offset by the lower rate of hospitalizations for CV-related disease. RM adoption generated savings of −€4,771 and −€6,752 per patient in 2 years, in the payer and hospital perspective, respectively.ConclusionRM of patients carrying CIED improves short-term (2-years) morbidity and mortality risks, compared to SM and reduces direct management costs for both hospitals and healthcare services
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